One of the main problems of SAR imagery is the presence of speckle noise, originated by the inherent coherent nature of this type of systems. For one-dimensional SAR systems it has been demonstrated that speckle can be considered as a multiplicative noise term. Nevertheless, this simple model cannot be exported when multidimensional SAR imagery is addressed. This paper is devoted to present the...

We consider linear multi-step methods for stochastic ordinary differential equations and study their convergence properties for problems with small noise or additive noise. We present schemes where the drift part is approximated by well-known methods for deterministic ordinary differential equations. Previously, we considered Maruyama-type schemes, where only the increments of the driving Wiene...

Spectral subband centroid, which is esse ntially the first -order normalized moment, has been proposed for speech recognition and its robustness to additive noise has been demonstrated before. In this paper, we extend this concept to the use of normalized spectral subband moments (NSSM) for robust speech recognition. We show that normalized moments, if properly selected, yield comparable recogn...

In this paper, we analyze the random fluctuations in a 1D stochastic homogenization problem and prove a central limit theorem: the first order fluctuations is described by a Gaussian process that solves an SPDE with an additive spatial white noise. Using a probabilistic approach, we obtain a precise error decomposition up to the first order, which also helps to decompose the limiting Gaussian p...

In the presence of background noise, the perceptual loudness of speech signal significantly decreases resulting in the deterioration of intelligibility and clarity. In this paper, we propose a novel approach to enhance the quality of speech signal when the additive noise cannot be directly controlled. Specifically, we propose an approach which reinforces the speech signal so that the partial lo...

In this paper a histogram enhancement technique is presented in order to improve the robustness of text-independent speaker verification systems. The technique transforms the features extracted from speech such that the contrast of their histogram is enhanced. Experiments showed significant improvements for this technique compared to standard techniques both in clean testing environments, and i...

This note presents the results from “Ergodicity of the degenerate stochastic 2D Navier-Stokes equation” by M. Hairer and J. C. Mattingly. We study the Navier-Stokes equation on the two-dimensional torus when forced by a finite-dimensional Gaussian white noise and give conditions under which the system is ergodic. In particular, our results hold for specific choices of four-dimensional Gaussian ...

We show that the capacity Cn,FB(P ) of the Gaussian channel with feedback is a concave function of P , and give two types of inequalities: both 1 α Cn,FB(αP ) and Cn,FB(αP ) + 1 2 ln 1 α are decreasing functions of α > 0. As their application we can obtain two upper bounds on the capacity of discrete time blockwise white Gaussian channel with feedback.

This paper deals with the problem of identifying the nature of noise and estimating its standard deviation from the observed image in order to be able to apply the most appropriate processing or analysis algorithm afterwards. In this study, we focus our attention on three classes of degraded noise images, the rst one being degraded by an additive noise, the second one by a multiplicative noise ...